International board acts on Lake Ontario water levels

by jmaloni

Sat, May 11th 2013 07:00 am

In
news of interest to area boaters and Lake Ontario property owners,
the International St. Lawrence River Board of Control has announced
its plan of maintaining current lake levels for the foreseeable
future.

The
board recently reviewed conditions in the Lake Ontario-St. Lawrence
River system and agreed to continue to store water on Lake Ontario
for future critical needs. Recently, the regulation plan was
responding to below-average Lake Ontario levels by prescribing Lake
Ontario outflows well below average for this time of year. As a
result, since the Ottawa River freshet that began in mid-April,
conditions downstream permitted only a limited amount of additional
water to be stored on the lake.

The
board reports that Lake Ontario is currently slightly above its
plan-specified level, but below its long-term average, as are the
other Great Lakes. The lake's under-discharge began when the level
on Lake St. Louis at Pointe Claire downstream in the St. Lawrence
River system reached a point at 1 foot lower than flood alert levels.

Currently,
the board is releasing water at a rate of 7,000 cubic feet per second
less than the plan-specified outflow from Lake Ontario. The board
will stop storing water in Lake Ontario if the water level at Pointe
Claire falls below intended levels for navigation and will resume
excess storage in Lake Ontario only if the level on Lake St. Louis is
at risk of exceeding its flood alert level. Property owners and
boating interests on Lake Ontario are reminded this plan itself
adjusts to water supplies, and a flow reduction of 7,000 cubic feet
per second in one week equates to approximately 0.2 inches of water
stored on Lake Ontario.

This
strategy will allow the board to address uncertainty in the inflows
during the freshet period. In addition, while the strategy will
provide environmental and recreational benefits of higher water
levels upstream on Lake Ontario, the extra water stored can also be
released later in the season to benefit commercial navigation and
boaters in the lower St. Lawrence River.

The
level on Lake Ontario as of May 1 was 245.57 feet, 26 inches above
the lower limit that applies from April 1 to Nov. 30, but 5 inches
below the long-term average level for this time of year. The level on
Lake St. Lawrence on May 1 was 241.83 feet, which is 3 inches above
average due to lower than average outflows through the Moses-Saunders
dam. The level at the Port of Montreal on May 1 was 24.51 feet, 1
inch above average.

At
the board's next review session, a decision will be made whether to
retain the stored water on Lake Ontario for gradual release over a
possibly dry summer and fall, or to release the extra water earlier,
in response to possibly wetter conditions.

Water
levels on both Lake Ontario and the St. Lawrence River vary
considerably from year to year depending on the weather conditions.
The board urges all interests to be prepared to live within the full
range of levels that have occurred.

The
board, in conjunction with its staff, continues to monitor the
situation carefully and is prepared to take further action as
required. The board will continue to review conditions and revise the
outflow strategy, if necessary. Outflow changes are posted to the
board's Facebook site at www.facebook.com/ISLRBC
(English) and its website at http://ijc.org/boards/islrbc/data
under Lake Ontario outflow changes.